Wetting agents and surface active compositions therefrom



United States Patent 3,219,584 WETTING AGENTS AND SURFACE ACTIVE COMPOSITIONS THEREFROM Alexander J. Stirton and Raymond G. Bistline, Jr., Philadelphia, James K. Weil, North Wales, and Waldo C.

Anlt, Glenside, Pa., assignors to the United States of America as represented by the Secretary of Agriculture N0 Drawing. Filed June 9, 1961, Ser. No. 117,491

17 Claims. (Cl. 252-109) (Granted under Title 35, U.S. Code (1952), see. 266) A non-exclusive, irrevocable, royalty-free license in the invention herein described, throughout the world for all purposes of the United States Government, with the power to grant sublicenses for such purposes, is hereby granted to the Government of the United States of Ameri- This invention relates to highly eflicient wetting agents which are salts of esters of ot-sulfonated fatty acids, to surface active compositions containing one or more of these wetting agents as an essential component, and to synergistic combinations containing these wetting agents.

An object of this invention is to provide wetting agents having a wetting time in the Draves test of less than seconds, preferably less than six seconds. Another object is to provide wetting agents which have good solubility in both Water and in oil. A further object is to provide improved wetting agents which exhibit stability under acidic or alkaline conditions, even at elevated temperatures. Other objects and a better understanding of the invention may be had by referring to the following description and claims.

The wetting agents of the present invention may be represented by the general formula where R is a normal alkyl radical containing 2 to 12 carbon atoms, M is sodium, potassium or ammonium, and R is a normal primary, branched chain primary, normal secondary, or branched chain secondary alkyl group containing 2 to carbon atoms or the H(CF CF CH group, and the sum of the carbon atoms in R plus R plus 2 is an integer from 14 to 19, inclusive. Expressed in another manner, the Wetting agents are the sodium, potassium or ammonium salts of alkyl or fluoroalkyl esters of O6-SlJlfO fatty acids.

As will be subsequently demonstrated in referring to the tabulated data, there are certain limitations as to the fatty acid or the alcohol which may be incorporated into the compounds of this invention, and especially in regard to the particular combinations of acids and alcohols. The fatty acid is limited to a normal saturated fatty acid containing from 4 to 14 carbon atoms, that is, butyric to myristic acids, inclusive. A large number of individual compounds are included in the scope of the general formula, however, because of the combinations obtainable in varyingthe alcohols and acids which are combined to form the esters. In the case of esters of a-sulfopelargonic acid, for example, the alcohol may be n-amyl, hexyl, heptyl, octyl, nonyl, decyl, or capryl (C H CHOHCH alcohol, 2-ethylhexanol, branched chain decyl alcohols, or dodecafluoroheptyl alcohol (H(CF CF CH OH). The compounds in Table I are presented to further illustrate some of the wetting agents of the present invention.

3,219,584 Patented Nov. 23, 1965 Molecular weight While most of the compounds are sodium salts, the most practical form cost-wise, these wetting agents may be prepared as potassium or ammonium salts if desired.

The wetting agents of our invention are characterized by very low wetting time values in standard tests used for the evaluation of wetting agents such as the Draves test using a cotton skein (Am. Dyestuff Reptr. 28, 425 (1939)), the Seyferth and Morgan canvas disk method (Am. Dyestuif Reptr., 27, 525 (1938)) or the Shapiro binding tape method (Am. Dyestutf Reptr. 39, 38 (1950)). The wetting agents of our invention at a concentration of 0.1% in aqueous solution have a wetting time value in the Draves test ranging from zero (or instantaneous wetting) to about 10 seconds, usually 6 seconds or less.

This very rapid wetting characteristic of the wetting agents of our invention is unexpected in View of the fact that the only recorded values for salts of alkyl esters of tt-sulfonated fatty acids range from 18 to 43 seconds at 0.1% concentration by the binding tape method (Stirton, Weil and Bistline, J. Am. Oil Chemists Soc., 31, 13 (1954) The wetting agents of our invention are further characterized by many desirable and useful properties. They are easily soluble in water, ethanol, ethyl ether, chloroform, parafiin oil and lubricating oil. They havelow surface and interfacial tension, adequate calcium stability in many cases and are useful in hard water. An outstanding advantage in contrast to present commercial wetting agents of the ester type, is the fact that they are not easily hydrolyzed and have wetting properties even in hot acid or alkaline solutions. Stability to hydrolysis arises from protection of the carboxylic acid ester group by the adjacent oc-SulfO group through steric hindrance.

The highly eflicient wetting agents of our invention are also characterized by critical micelle concentration (C.M.C.) values in the range (IS-16.0 millim'oles/l. For a given homologous series, such as the pelargonates, the most efficient members demonstrate correlation between low surface and interfacial tension, C.M.C. and low wetting time values,

The wetting agents of our invention need not be chemically pure individual compounds in order to be useful. Thus, mixtures of two or more of the salts of esters of u-sulfonated fatty acids of Table I constitute effective wetting agents. Furthermore we have discovered that a commercial fatty acid mixture can be used in place of a chemically pure fatty acid. Thus a product based on coconut oil fatty acid foreruns and 2-ethylhexan0l is an efficient wetting agent. In this case the coconut oil fatty acid forerun is a mixture of caproic, caprylic, capric, lauric and myristic acids which 'has an average composition approximating that of decanoic acid. A representative formula for the salt of the ester of the a-sulfonated fatty acid mixture is C I-I CH(SO Na)CO C H where the total number of carbon atoms R+R'+2 in the formula is 8+8+2 or 18, in agreement with the scope of our invention.

Another object of our invention is to provide mixtures of individual esters which are synergistic in behavior.

Sodium alkyl a-sulfopalmitates and sodium alkyl oc-SlllfO- stearates do not have pronounced wetting properties but we have discovered that mixtures of these or of sodium salts of alkyl esters of u-sulfonated tallow acids with the Wetting agents of our invention have wetting properties superior to the contribution of either ester alone. Thus a mixture of 0.05 each of sodium alkyl u-sulfo pelargonate and sodium alkyl u-sulfostearate has a lower wetting time than the sum of the time for the two surface active agents alone at 0.05% concentration, or the average for the two surface active agents at 0.1% concentration.

This synergism is particularly evident in hard water.

Synergism need not derive from a simple mixture of two chemically pure sodium salts of alkyl esters of a-sulfonated acids but may derive from readily available industrial fatty acids such as a combination of hydrogenated coconut oil fatty acids with hydrogenated tallow fatty acids. Thus a mixture of hydrogenated coconut -oil fatty acids and hydrogenated tallow fatty acids is sulfonated with the vapor of sulfur trioxide, esterified with secondary butyl alcohol and neutralized to form the sodium salt of the butyl esters of the a-sulfonated fatty acids.

Another object of our invention is to provide improved wetting agent compositions particularly useful in very hard water and in the presence of various metal ions. We have discovered that certain wetting agents of our invention which are not quite as useful in hard as in soft water can be improved by the presence of a builder .systems as well as insecticidal sprays, industrial emulsifying agents and addition agents to lubricants.

The wetting agent of our invention are useful with soap and other detergents in 'hard water, suitably in synergistic mixtures with builders such as pyrophosphates and tripolyphosphates.

The wetting agents of our invention may be prepared by a variety of methods. The method may be selected on the basis of the particular structure desired. Thus an ester of the general formula RCH(SO M)CO R' where R is C H M is K and R is C H specifically potassium butyl a-sulfomyristate (Table I) may be prepared by the reaction of a-sulfomyristic acid with butyl alcohol and neutralization by potassium hydroxide or potassium carbonate; or precipitation and separation by addition of 4 inorganic potassium salts. No esterification catalyst is required because the sulfonic acid group of a-sulfomyristic acid constitutes the esterification catalyst.

Esters of OL-SlJlfO acids and alcohols of nearly equal chain length such as sodium hexyl u-sulfopelargonate (Table I) can be prepared by the reaction of sodium a-sulfopelargonic acid with hexyl alcohol, catalyzed by sulfuric acid, in the presence of benzene, toluene or xylene to remove water of esterification azeotropically.

Esters of shorter chain a-sulfo acids and longer chain fatty alcohols, for example sodium decyl u-sulfocaproate (Table I) may be prepared by the reaction of u-sulfocaproic acid with decanol. The oc-sulfocaproic acid formed by the reaction of caproic acid with sulfur trioxide, need not be isolated. Decanol may be added to the sulfon-ation reaction mixture with an aromatic hydrocarbon included to remove water of esterification azeotropically. On completion of the reaction the mixture is neutralized with aqueous NaOH or the sodium salt of the desired ester is precipitated by addition of an inorganic sodium salt.

Other means for the formation of the esters of our invention include the reaction of the barium salt of an OL-SlllfO fatty acid, from butyric to myristic acid, with an alcohol of the requisite number of carbon atoms, in the presence of an aromatic hydrocarbon to remove water of esterification azeotropically, and in the presence of a slight excess of sulfuric acid. The barium sulfate precipitated is removed and the ester can be isolated as the Na, K or NH; salt. Still another means is the replacement of a halogen atom in the ester RCHXCO R by means of an inorganic sulfite. The following examples illustrate but do not limit the nature and scope of our invention.

EXAMPLE 1.SODIUM HEXYL a-SULFOPELARGONATE Analysis.Calculated for C H NaO S: 6.68% Na,

9.31% S. Found: 6.59% Na, 8.95% S.

The sodium a-sulfopelargonic acid can be prepared by the sulfonation of pelargonic acid with liquid sulfur trioxide in the presence of carbon tetrachloride as the solvent, or by sulfonation with sulfur trioxide vapor in the absence of solvent as described in our publication [Weil, Stirton, Bistline, Jr., and Ault, J. Am. Oil Chemists Soc., 37, 679-682 (1960)].

EXAMPLE 2.-SODIUM CA-PRYL a-SULFOPELARGONATE Sodium a-sulfopelargonic acid was esterified with capryl alcohol (octanol-Z) after the manner of Example 1. Sodium capryl a-sulfopelargonate was isolated in a pure state in a yield of 65%.

Analysis.Calculated for C H NaO S: 54.81% C, 8.93% H, 6.17% Na, 8.61% S. Found: 54.37% C, 9.19% H, 6.07% Na, 8.79% S.

EXAMPLE 3.SODIUM NONYL OL-SULFO- PELARGONATE Esterification of sodium ot-sulfopelargonic acid with nnonanol after the manner of Example 1 gave sodium nonyl a-sulfopelargonate in a pure state in a yield of 70%.

Analysis.-Calculated for C H NaO S: 5.95% Na, 8.30% S. Found 5.82% Na, 8.24% S.

.. 5 EXAMPLE 4.SODIUM OX DEC'YL a-SULFOPELARGONATE A commercial decyl alcohol from the 0x0 process (a mixture of isomeric 10 carbon atom primary alcohols, predominantly isomeric trimethylheptanols) was esterified with sodium u-sulfopelargonic acid after the manner of Example 1. Sodium oxo decyl a-sulfopelargonate was obtained as a light. yellow product.

Analysis.Calculated for C H NaO S: 5.74% Na. Found 5.80% Na.

EXAMPLE 5 .-SODIUM' 1H, lH,7H-DODECA- 'FLUORO-l-HEPTYL oc-SULFOPELARGONATE Sodium a-sulfoperlargonic acid was esterified with 1H, 1H,7H-dodecafluoro 1 heptanol[H(CF CF CH OH] in a manner similar to Example 1. The product ester was a white solid.

A nalysis.--Calculated for C H CH(SO Na)CO OH (CF CF H 4.00% Na. Found 3.98% Na.

EXAMPLE 6.--SODIUM AMYL u-SULFOLAURATE a-Sulfolauric acid was prepared by vaporizing 60 ml. of liquid sulfur trioxide and leading the vapor mixed with nitrogen into a stirred solution of 202 g. of lauric acid in 250 ml. of chloroform and 250 ml. of carbon tetrachloride during 3 hrs. at 30-45 C. The sulfonation mixture was further heated to 60 C., refrigerated at 20 C., filtered and dried over calcium sulfate. a-Sulfolauric acid was obtained as a gray solid.

Analysis.Calculated for C H NaO S: neutralization "equivalent (N.E.) 1 40.2. Found 134.2. Aportion was converted to the monosodium salt by means of sodium chloride.

Analysis.Calculated for C H NaO S: 7.60% Na, N.E. 302.4. Found 7.55% Na, N.E. 302.3.

A mixture of 28 grams of u-sulfolauric acid, 11.5 ml. of n-amyl alcohol and 200 ml. of toluene was heated and stirred for 2.5 hours at the refluxtemperature with azeotropic removal of water. The reaction mixture was neutralized with aqueous sodium hydroxide and evaporated with recovery of toluene and excess n-amyl alcohol. The residue was treated with absolute ethanol, inorganic salts were removed, water was added and the product was crystallized from aqueous ethanol at 20 C. to give sodium amyl u-sulfolaurate.

Analysis.-Calculated for C17H33N21O5SZ 6.17% Na. Found 5.98% Na.

EXAMPLE 7.POTASSIUM BUTYL a-SULFOMYRISTATE a-Sulfomyristic acid was esterified with an excess of nbutanol at reflux temperature with azeotropic removal of water. Potassium butyl a-sulfomyristate was obtained as a white product in a yield of 55% Analysis.Calculated for C H KO S: 9.71% K. Found 9.90% K.

The a-sulfomyristic acid may be prepared by a method we have previously described Weil, Bistline, Jr., and Stirton, Organic Syntheses, 36, 83-86 (1956)).

EXAMPLE 8-SODIUM DODECYL a-SULFOBUTYRATE The barium salt of u-sulfobutyric acid 6 was prepared by the sulfonation of butyric acid with sulfur trioxide and the isolation of the product as the barium salt.

Analysis.Calculated for C H BaO S: 45.26% Ba. Found 45.26% Ba.

A stirred mixture of 0.1 mole (30.4 g.) of barium asulfobutyrate, 0.11 mole (20.4 g.) of dodecanol, 11 g. of concentrated H and 200 ml. of toluene was refluxed 3 hours with azeotropic removal of water and neutralized with alcoholic NaOH. After removal of BaSO by filtration, and unreacted dodecanol by ether extraction of an aqueous alcohol solution, the extracted solution was evaporated to give a 63% yield of sodium dodecyl a-sulfobutyrate.

Analysis.-Calculated for C H NaO S: 6.42% Na. Found 6.27% Na.

EXAMPLE 9.SODIUM SALT OF Z-ETHYLHEXYL ESTER OF a-SULFONATED COCONUT OIL FATTY ACID FORERUN A commercial coconut oil fatty acid forerun was used, (a mixture of about 42% caprylic, 28% capric, 24% lauric and 6% myristic acid, neutralization equivalent 169.3) corresponding to decanoic acid on the average.

Sulfur trioxide vapor mixed with nitrogen, containing grams (1.12 moles) of sulfur trioxide was passed into the semi-liquid coconut oil fatty acid forerun, 161 grams (0.95 mole), at 14 C., with agitation. The temperature of the viscous reaction mixture reached a maximum of 64 C. Toluene and 2-ethylhexanol were added and the sulfonated fatty acids were esterified with azeotropic removal of water. The reaction mixture was neutralized with sodium hydroxide and the product was isolated after recovery of solvent as the sodium salt of the 2-ethylhexyl ester of a-sulfonated coconut oilfatty acid foreruns.

Analysis.Calculated for C H NaO S: 5.95% Na. Found 6.44% Na. The product may contain about 8% inorganic salts.

Properties The surface active and related properties of the Wetting agents of our invention are illustrated in Table II. With the exception of compounds included for comparison, all of the compounds listed arewetting agents which come within the scope of our invention. The compounds included for comparison are potassium hexadecyl uc-SlllfO- propionate, sodium ethyl and dodecyl a-sulfopelargonate, sodium methyl and dodecyl oa-sulfolaurate, and sodium methyl a-sulfopalmitate.

The wetting agents of our invention listed in Table II have wetting times by the Draves test (0.1% solution, 5 g. cotton skein, 3 g. hook, 40 g. anchor) of 6 seconds or less. They may be more efficient in soft than in hard water, or more efiicient in hard water or may be about equally eflicient in soft and hard water. The most efficient of Table II are characterized by low surface and interfacial tension and a critical micelle concentration in the range of about 1-7 millimoles/l. These are sodium dodecyl a-sulfobutyrate, sodium hexyl, heptyl, capryl, and 2-ethylhexy1 a-sulfopelargonate, sodium 2-ethylhexyl usulfo coconut oil fatty acid forerun, sodium propyl, butyl and amyl a-sulfolaurate and potassium butyl a-sulfomyristate.

The calcium stability ranges from about 300 to 1800 p.p.m. calculated as calcium carbonate, and so all of the wetting agents are useful, with different degrees of efficiency, in hard water of the degree of hardness normally encountered; and a few are useful inthe presence of very large concentrations of the calcium ion.

The most eflicient wetting agents of Table H have excellent foaming properties in either soft or hard water 3 di(2-ethylhexyl) sulfosuccinate. The results are shown in Table III.

TABLE III.-WETTING TIME AND CONCENTRATION Wetting time, seconds, solutions in distilled water, Draves test at various wetting agent Wetting Agent concentrations.

Sodium heptyl a-sulfopelargonate 10. 2 2. 8 1. 7 2 0. Sodium octyl a-suliopelargonate..- 13.2 5. 0 2. 6 1. 3 2 0. 0 Sodium capry] a-sulfoperlagonate.. 9. 6 3. 7 2. 2 1. 3 2 0.0 Sodium 2-ethylhexyl a-sultopclargonate- 10. 5 2. 7 1. 5 2 0.0 Sodium butyl a-sultolaurate 13. 2 4. 3 2. 3 1. 6 2 0. 0 Sodium amyl a-sulfolaurate 11.2 4. 2 2. 4 1. 9 2 0.0 Sodium di(2-ethylhexyl) suliosuceinate 16. 2 4. 9 2. 8 1. 7 2 0.0

1 Commercial wetting agent. 2 Instantaneous.

TABLE 11.-PROPERTIES OF WEITING AGENTS Surface and Inter- Wetting Time Draves facial Tension, test 0.1% solution, Foam, 60 C. 0.25% Detergency b dynes/cm. 0.2% C.M.C., seconds Ca++ solutions, mm. Launder- Alcohol R OH solns. millistability, Ometer 0.25%

moles p.p.m. solutions per liter 60 0. AR S.T. LT. Distd. 300 Distd. 300

p.p.rn. p.p.m.

K Hexadecyl a-Sulfopropionate 35. 5 5. 3 .2 58.0 300 480 Na Dodecyl a-Sulfobutyrate 36. 8 9. 1 1. 9 5. 5 4. 4 1, 800 200 225 27 Na Alkyl a-sultopelargonatcsz C H OH 52.9 39. 8 98.0 300 300 1, 800 4 0 10 40. 3 18. 9 16.0 12. 1 5. 3 310 80 140 26. 8 7. 1 7. 0 2. 2 1. 4 290 210 240 23 26. 6 5. 7 4. 5 1. 5 4. 7 440 210 240 26 25. 7 4. 5 2. l 1. 3 13. 2 500 230 220 31 26. 4 4. 8 3. 6 1. 3 4. 5 520 220 230 25 25. 9 3. 9 1. 9 0.0 4. 5 530 240 175 17 25. 4 3. 8 1. 2 3. 8 33. 1 500 230 80 31 25. 0 3.0 0. 5 6. 0 105. 0 610 240 30 21 23. 6 1. 7 0. 5 1. 6 34. 8 310 250 30 19 25.2 1. 0 0. 1 103. 0 300 750 210 20 26 19. 1 5. 6 2. 4 3. 6 24. 8 350 265 30 20 Na Alkyl a-SlllfO Coconut Oi Fatty Acid Forerun:

BuCHEtCHzOH 25.3 1. 5 3. 5 5. 5 500 220 150 Na Alkyl a-Sultolaurates:

OH OH 28. 3 11.1 10. 9 57. 6 34. 3 1, 800 170 210 16 31. 9 7. 9 7. 8 10. 5 5. 4 1, 800 130 210 22 35. 5 9. 5 5. 4 3. 2 2. 0 1, 800 210 230 25 33.8 8. 7 2. 8 1. 6 1. 5 730 220 230 24 31. l 6. 9 1. 7 1. 6 4. 9 500 220 235 26 28. 1 4. 6 0. 9 2. 2 39. 5 570 230 180 23 CuHzsOH 25.6 3. 8 300 300 140 20 30 K Alkyl a-sulfomyrista es.

C H OH 31. 6 4. 5 0. 6 4. 8 5. 2 500 215 240 32 N a Alkyl a-sulfopalmitatesz CH3OH 39. 0 9. 7 0.4 25.0 15. 5 1, 800 205 225 31 a Critical Micelle Concentration.

b AR=increase in reflectance after washing; AR for 0.25% Na dodecgl sulfate in distd. water=28.0.

and give a stable and attractive foam. Although excellent wetting characteristics are usually associated with rather mediocre detergent properties several of the Wetting agents of our invention have good detergency as well as excellent wetting characteristics.

Wetting time and concentration The wetting time of 6 of the most efficient wetting agents of our invention was measured by the Draves test (5 g. cotton skein, 3 g. hook) at concentrations from 0.025% to 0.15% in distilled water, in comparison with the highly eflicient commercial wetting agent, sodium Stability to hydrolysis In Table IV the rate of hydrolysis of esters of a-sulfo fatty acids is compared with that for the commercial wetting agent, sodium di(2-ethylhexyl) sulfosuccinate.

TABLE IV.RATE CONSTANTS, ACID AND ALKALINE HYDROLYSIS [k (N/3 H2504) =1/t 1n g minutes 100 T). k2 (N /10 NaOH) =1/t i liters/mole/minute, 100 C.]

Acid Alkali k1 Relative kg Relative Rate Rate Sodium Methyl a-Sulfopalmitate CuHzoCH 0047 30 0 14 16 S O 3N8.

Sodium Hexyl a-sulfopelargonate C ozCuHia OrHraCH 0. 0020 13 0. 16 18 S O 3N3 Sodium Capryl a-Sulfopelargonate C 02011 CaHrs S O aNa Sodium Di(2-Ethy1hexyl)- Sulfosuccinate B 0. 0156 100 0.9 100 oz 0. 0033 21 Approx.

Acid catalyzed hydrolysis, heating 0.1 gram equivalent at 100 C. in the presence of N/ 3 H 50 was found to be a first order reaction. The a-sulfo group protects the adjacent :carboxylic acid ester group through steric hindrance. The sulfosuccinate ester was found to have 2 reaction rate constants in acid catalyzed hydrolysis. Hydrolysis takes place rapidly at first at the B ester linkage In Table V the wetting time for sodium capryl oc-SlllfO- pelargonate, sodium heptyl a sulf-opelargonate, and sodium di(2-ethylhexyl) sulfosuccinate is compared, in neutral, acid and alkaline solution at 25 C., and again after heating in acid and alkaline solution at 100 C. for a specified time, cooling and re-determining the wetting time.

TABLE V. STABILITY TO HYDROLYSIS. WETTING PROPERTIES IN ACID AND ALKALI Wetting Time, seconds, Draves Test, 5 g. skein, 3 g. hook, 0.17;

concentration, 0.

Surface Active Agent Boiled In- Boiled In Distd. 5% 1% Water H 5% for H280 NaOH 1% for NaOH Hour for Hour for 1 Hour 1 Hour Sodium Methyl a-sulfopalmitaten. 25. 0 28. 2 36. 8 36. 5 36. 8 600 Sodium Capryl* wSuliopelargonate 1. 3 3. 5 5. 8 6. 6 4. 4 8. 0 21. 2 Sodium Heptyl a-Sulfope1argonate 0.0 3. 0 4. 1 4. 5 3. 4 600 Sodium Di(2-Ethylhexyl) Sulfosuccinate 2.3 3.8 600 3 3 600 *Ester 0f CH3CHOHC5H13.

CH CO CH CH(C H )C H of the sulfosuccinate since this is unprotected by an adjacent sulfo group. The reaction rate constant, k (/3)=0.0l56. All wetting properties were lost in this initial stage of hydrolysis. Hydrolysis .at the ester group adjacent to the sulfo group then proceeded at a much slower rate, k (a)=0.0033, comparable to the value for sodium hexyl a-sulfopelargonate, k =0.0020, and sodium methyl a-sulfopalmitate, k =0.0047. Sodium capryl a-sulfopelargonate, an ester of a secondary alcohol, hydrolyzed at the slowest rate, k :0.0010. Comparative rates are shown in Table IV.

Alkaline hydrolysis is a second order reaction. Under these conditions hydrolysis of the sulfosuccinate was too rapid to measure in separate stages; accordingly a reaction rate at the midpoint of hydrolysis, k =0.9, was taken and rates were expressed relative to this value. Sodium capryl a-sulfopelargonate, an ester of a secondary alcohol, is seen to be especially resistan to either acid or alkaline hydrolysis.

The sulfosuccinate lost all wetting properties after heating in either acid or alkaline solution. The sodium heptyl a-sulfopelargonate retained its wetting properties in boiling 5% H solution, and sodium capryl a-sulfopelargonate continued to have good wetting properties in hot acid solution and in hot 1% NaOH solution as well. This stability to hydrolysis increases the field of usefulness for the wetting agents of our invention.

Synergistic compositions Table VI demonstrates that the wetting agents of our invention, particularly those which are not as efficient in hard as in soft water, are improved by the presence of a builder which in the particular data cited is a mixture of 56% sodium tripolyphosphate, 24% sodium sulfate, 10% sodium pyrophosphate, and 10% sodium metasilicate. The improvement is synergistic and is beyond that to be expected or predicted.

Distilled Water Hard Water, 300 p.p.m.

Unbuilt Built RCH(SO Na)C R 0 057 0 107 percent percent Na Oct 1 -Sulf0pelargonate L- 5.0 1.3 21.2 13.2 5.0 4.0 Na Nori yl a-sulfopelargonate 8. 8 3. 8 40. 8 33. 1 13. 6 8. 2 Na Decyl a-sulfopelarglofiiata I 24. 8 6. 0 130.0 105. 0 43. 3 31. 6 Na Salt of Z-Ethylhexy ster o nut Oil Fatty Acid Forerun IL- 10. 8 3. 5 40.2 7. 0 16. 2 6. 0 Na Methyl a-Sulfostearate III 59. 0 46. 6 300 91.0 58.8 59. 5 Na Isopropyl a-Suliostearate IV 84. 0 82. 0 163. 0 68. 3 100. 0 58. 4 Mixtures:

0. 05% I+0.05% III... 9. 5 10.0 8.0 0.05% I-l-0.05% IV. 9. 0 10.0 10.0 0.05% II+0. 05% Ill 12. 7 14.6 14.3

Builder, B, has the composition 56% sodium tripolyphosphate, 24% sodium sulfate, 10% sodium pyrophosphate and 10% sodium metasilicate.

Synergism in mixtures of sodium alkyl a-sulfopelargonates with builders is shown in the fact that in hard water the wetting time for the octyl, nonyl and decyl esters at 0.05% concentration (21.2, 40.8, 130.0 seconds) is reduced to 5.0, 13.6, 43.3 seconds respectively; at 0.10% concentration (13.2, 33.1, 105.0 seconds) to 4.0, 8.2, 31.6 seconds, respectively; and particularly by the fact that the wetting time at 0.10% concentration is reduced by decreasing the concentration to 0.05% and adding builder. Thus wetting time values of 13.2, 33.1 and 105.0 seconds are reduced to 5.0, 13.6 and 43.3 seconds, respectively even though only half as much wetting agent is used.

Synergism in mixtures of the wetting agents of our invention with sodium alkyl ot-sulfopalmitates and sodium alkyl a-sulfostearates is shown in Table VI. Thus in distilled water a mixture of 0.05% I-|-0.05% III has a wetting time (9.5 seconds) less than the sum of the Wetting times for 0.05% I and 0.05% III alone, (64.0 seconds) and less than the average of the sums for 0.10% I and 0.10% III alone (24.0 seconds). Like synergism in distilled water solution is shown for mixtures of I with IV and mixtures of II with III. Synergism is also shown for each of the mixtures in solutions in hard water and for solutions in hard water in the presence of builder.

Sodium alkyl a-sulfopalmitates and sodium salts of alkyl esters of u-sulfonated hydrogenated tallow acids are also synergistic in wetting properties with the wetting agents of our invention.

Detergent compositions The data of Table VII show that the wetting agents of our invention have good detergent properties in hard and moderately hard water in the presence of builder, and can also be used in built detergent compositions with soap and with sodium salts of a-sulfonated hydrogenated tallow acids, as typified by sodium methyl a-sulfostearate. The builder used is that of Table VI. For comparison the AR values for 0.25% sodium dodecyl sulfate are 21 and 24 in 150 and 300 p.p.m., respectively.

TAB LE VII.-DETE R GENT C OMPOSITIONS *Increase in reflectance after Washing.

We claim: 1. A wetting agent composition effective in distilled and hard water consisting of about from to 80% 25 by weight of a member selected from the group consisting of a sodium alkyl ot-sulfopelargonate, a sodium alkyl a-sulfolaurate, a sodium alkyl a-sulfomyristate, each alkyl containing from 2 to 12 carbon atoms, inclusive, the sodium salts of the 2-ethylhexyl esters of the a-sulfonated coconut oil fatty acids, and about from 80% to 20% by weight of a member selected from the group consisting of the sodium salts of the methyl esters of a-sulfonated hydrogenated tallow acids, the sodium salts of the isopropyl esters of ot-sulfonated hydrogenated tallow acids, sodium methyl a-sulfostearate, sodium isopropyl a-sulfostearate, sodium methyl u-sulfopalmitate, and sodium isopr-opyl oesulfopalmitate.

2. A wetting agent composition eifective in distilled and hard water consisting of 50% by weight of sodium octyl a-sulfopelargonate and 50% by weight of sodium 4. A wetting agent composition effective in distilled and hard water consisting of by weight of sodium methyl a-sulfostearate and 50% by weight of the sodium salts of the 2-ethylhexyl esters of the a-sulfonated coconut oiI fatty acids.

50 5. A wetting and detergent composition effective in hard water consisting of about from 10% to 40% by weight of a member selected from the group consisting of a sodium alkyl a-sulfopelargonate wherein the alkyl contains from 2 to 12 carbon atoms, inclusive, sodium dodecafluoroheptyl a-sulfopelargonate, sodium hexyl a-sulfolaurate, the sodium salts of the Z-ethylhexyl esters of the u-sulfonated coconut oil fatty acids, and mixtures of said members, and from 90% to by weight of an inorganic builder consisting of 56% sodium tripoly- 60 phosphate, 24% sodium sulfate, 10% sodium pyrophosphate, and 10% sodium metasilicate.

6. A wetting and detergent composition eifective in hard water consisting of 20% by weight of a sodium alkyl a-sulfopelargonate wherein the alkyl contains from 2 to 12 carbon atoms, inclusive, and 80% by weight of an inorganic builder consisting of 56% sodium tripolyphosphate, 24% sodium sulfate, 10% sodium pyrophosphate, and 10% sodium metasilicate.

7. A wetting and detergent composition eifcctive in hard water consisting of 20% by weight of sodium octyl a-sulfopelargonate and 80% by weight of an inorganic builder consisting of 56% sodium tripolyphosphate, 24% sodium sulfate, 10% sodium pyrophosphate, and 10% sodium metasilicate.

8. A Wetting and detergent composition effective in hard water consisting of 20% by weight of s dium nonyl a-sulfopelargonate and 80% by weight of an inorganic builder consisting of 56% sodium tripolyphosphate, 24% sodium sulfate, 10% sodium pyrophosphate, and 10% sodium metasilicate.

9. A wetting and detergent composition effective in hard water consisting of 20% by weight of the sodium salts of the Z-ethylhexyl esters of the a-sulfonated coconut oil fatty acids, and 80% by weight of an inorganic builder consisting of 56% sodium tripolyphosphate, 24% sodium sulfate, 10% sodium pyrophosphate, and 10% sodium metasilicate.

10. A wetting and detergent composition effective in hard water consisting of about from to 25% by weight of a member selected from the group consisting of a sodium alkyl a-sulfopelargonate, a sodium alkyl a-sulfolaurate, a sodium alkyl a-sulfomyristate, each alkyl containing from 2 to 12 carbon atoms, inclusive, the sodium salts of the 2-ethylhexyl esters of the a-sulfonated coconut oil fatty acids, about from 5% to 25% by weight of a member selected from the group consisting of the sodium salts of the methyl esters of a-sulfonated hydrogenated tallow acids, the sodium salts of the isopropyl esters of a-sulfonated hydrogenated tallow acids, sodium methyl a-sulfostearate, sodium isopropyl m-sulfostearate, sodium methyl a-sulfopalmitate, sodium isopropyl wsulfopalmitate, and about from 90% to 50% by weight of an inorganic builder consisting of 56% sodium tripolyphosphate, 24% sodium sulfate, sodium pyrophosphate, and 10% sodium metasilicate.

11. A wetting and detergent composition effective in hard water consisting of 20% by weight of a mixture of equal amounts by Weight of sodium octyl u-SlllfO- pelargonate and sodium methyl a-sulfostearate, and 80% by weight of an inorganic builder consisting of 56% sodium tripolyphosphate, 24% sodium sulfate, 10% sodium pyrophosphate, and 10% sodium metasilicate.

12. A wetting and detergent composition effective in hard Water consisting of 20% by weight of a mixture of equal amounts by Weight of Sodium octyl asulfopelargonate and sodium isopropyl a-sulfostearate, and 80% by weight of an inorganic builder consisting of 56% sodium tripolyphosphate, 24% sodium sulfate, 10% sodium pyrophosphate, and 10% sodium metasilicate.

13. A Wetting and detergent composition effective in hard water consisting of about from 5% to 25% by Weight of a member selected from the group consisting of a sodium alkyl a-sulfopelargonate, a sodium alkyl ot-sulfolaurate, a sodium alkyl a-sulfomyristate, each alkyl containing from 2 to 12 carbon atoms, inclusive, and the sodium salts of the 2-ethylhexy1 esters of the u-sulfonated coconut oil fatty acids, about from 5% to 25% by weight of a member selected from the group consisting of the sodium soaps of the fatty acids of tallow and the sodium soaps of the fatty acids of coconut oil, and about from 90% to 50% by weight of an inorganic builder consisting of 56% sodium tripolyphosphate, 24% sodium sulfate, 10% sodium pyrophosphate, and 10% sodium metasilicate.

14. A wetting and detergent composition effective in hard water consisting of about 20% by weight of the sodium salts of the Z-ethylhexyl esters of the a-sulfonated coconut oil fatty acids, about 20% by Weight of soap flakes, and about 60% by weight of an inorganic builder consisting of 56% sodium tripolyphosphate, 24% sodium sulfate, 10% sodium pyrophosphate, and 10% sodium metasilicate.

15. A wetting and detergent composition effective in hard water consisting of about from 10% to 40% by Weight of a member selected from the group consisting of a sodium alkyl a-sulfopelargonate wherein the alkyl contain from 2 to 12 carbon atoms, inclusive, sodium dodecafluoroheptyl a-sulfopelargonate, sodium hexyl u-sulfolaurate, the sodium salts of the Z-ethylhexyl esters of the a-sulfonated coconut oil fatty acids, and mixtures of said members, and about from to 60% by weight of an inorganic builder.

16. A wetting and detergent composition effective in hard water consisting of about from 5% to 25% by Weight of a member selected from the group consisting of a sodium alkyl et-sulfopelargonate, a sodium alkyl a-sulfolaurate, a sodium alkyl ot-sulfomyristate, each alkyl containing from 2 to 12 carbon atoms, inclusive, and the sodium salts of the Z-ethylhexyl esters of the a-SlllfOllflted coconut oil fatty acids, about from 5% to 25% by weight of a member selected from the group consisting of the sodium salts of the methyl esters of a-sulfonated hydrogenated tallow acids, the sodium salts of the isopropyl esters of u-sulfonated hydrogenated tallow acids, sodium methyl a-sulfostearate, sodium isopropyl a sulfostearate, sodium methyl a-sulfopalrnitate, sodium isopropyl u-sulfopalmitate, and about from 90% to 50% by weight of an inorganic builder.

17. A Wetting and detergent composition effective in hard Water consisting of about from 5% to 25% by weight of a member selected from the group consisting of a sodium alkyl a-sulfopelargonate, a sodium alkyl a-sulfolaurate, a sodium alkyl wsulfomyristate, each alkyl containing from 2 to 12 carbon atoms, inclusive, and the sodium salts of the 2-ethylhexyl esters of the u-sulfonated coconut oil fatty acids, about f om 5% to 25% by weight of a member selected from the group consisting of the sodium soaps of the fatty acids of tallow and the sodium soaps of the fatty acids of c 00- nut oil, and about from 90% to 50% by Weight of an inorganic builder.

References Cited by the Examiner UNITED STATES PATENTS 2,043,476 1/1936 Guenther et al 260400 2,316,194 4/1943 Toone et al 252354 XR 2,460,968 '2/1949 Ber-t et a1. 260-4OO 2,486,921 11/1949 Byerly 252-l38 2,867,586 1/1959 Wiel et a1. 252-354 XR 2,979,466 4/1961 Sil'berman 252l38 2,990,375 6/1961 Steinhauer et al 252138 JULIUS GREENWALD, Primary Examiner.

ALBERT T. MEYERS, Examiner. 

1. A WETTING AGENT COMPOSITION EFFECTIVE IN DISTILLED AND HARD WATER CONSISTING OF ABOUT FROM 20% TO 80% BY WEIGHT OF A MEMBER SELECTED FROM THE GROUP CONSISTING OF A SODIUM ALKYL A-SULFOPELARGONATE, A SODIUM ALKYL A-SULFOLAURATE, A SODIUM ALKYL A-SULFOMYRISTATE, EACH ALKYL CONTAINING FROM 2 TO 12 CARBON ATOMS, INCLUSIVE, THE SODIUM SALTS OF THE 2-ETHYLHEXYL ESTERS OF THE A-SULFONATED COCONUT OIL FATTY ACIDS, AND ABOUT FROM 80% TO 20% BY WEIGHT OF A MEMBER SELECTED FROM THE GROUP CONSISTING OF THE SODIUM SALTS OF THE METHYL ESTERS OF A-SULFONATED HYDROGENATED TALLOW ACIDS, THE SODIUM SALTS OF THE ISOPROPYL ESTERS OF A-SULFONATED HYDROGENATED TALLOW ACIDS, SODIUM METHYL A-SULFOSTERATE, SODIUM ISOPROPYL A-SULFOSTERATE, SODIUM METHYL A-SULFOPALMITATE, AND SODIUM ISOPROPYL A-SULFOPALMITATE. 